System to rid space station of astronaut exhalations inspires Earth-based CO2 removal

From people who get grants, but may be thermodynamically challenged.~ctm

November 13, 2018 by Anthony King, From Horizon Magazine

The International Space Station air filter which expels CO2 has inspired scientists to try to create an Earth-based version. Credit: NASA/Mark Garcia

When astronauts aboard the International Space Station (ISS) exhale carbon dioxide (CO2), it’s removed from the air and pumped into space. Could an Earth-based version help remove greenhouse gas emissions from our atmosphere?

One way of doing this is to cut emissions. Another is to design materials that can remove the CO2 that is already in the atmosphere or before it’s expelled. The problem is that no one has quite worked out how best to do this – yet.

The air filter system in space inspired Professor Stefano Brandani and Dr. Giulio Santori from the University of Edinburgh, UK, to develop a way of capturing and concentrating CO2 directly from the atmosphere. This ambitious strategy – to build a so-called artificial tree – would see CO2 captured to be stored in large underground reservoirs.

Zeolite

The CO2 breathed by astronauts aboard the ISS is captured by using a sponge-like mineral called a zeolite, which has tiny pores to lock in a CO2 molecule. On the space station, the zeolites empty their CO2 when exposed to the vacuum of space.

As part of a project called ACCA, Dr. Santori is hacking the system so it will work on Earth. This is more challenging. “There is so much more CO2 to capture and concentrations are more dilute to begin with on Earth, so it is much more energy intensive,” he explained. “The starting concentration of CO2 on the ISS is one order of magnitude higher.”

The new system works by having a series of zeolite adsorption beds. Each takes in CO2, concentrates it a little and releases it when heated up. “It is like a sponge. You regenerate the material using heat. When it is cold, it takes in a lot (of CO2),” said Dr. Santori.

This CO2 then moves into a new adsorption bed, which again pushes the gas molecules closer. The gas is thereby compressed more at each step, without the need for moving parts like vacuum pumps. Temperature changes are the engine of this process. Heating and cooling the spongy material causes it to release the gas, and take up more.

With five beds of zeolites, emptied with heat – which could be waste heat from an industrial facility – and cooled at ambient temperature, CO2 could be captured at a purity of above 95%, with little energy consumed.

“If you could capture CO2 from the air, this will allow you compress it and to store it in a nearby geological facility,” said Dr. Santori, who believes that large-scale carbon capture and storage is the ideal strategy for decreasing CO2 in the atmosphere.

The CO2 breathed by astronauts aboard the ISS is captured by using a sponge-like mineral called a zeolite. Credit: Pictures are in the public domain

In the long term, zeolites could be used in stations that could capture CO2 directly from the air – but this is a long way off as compressing CO2 is just part of the problem. Because CO2 is very dilute in ambient air, technology such as giant fans would be needed to suck it towards the stations without spending too much energy or money – something that is still too high a hurdle for current technologies. Prof. Brandani said: “The issue is how much it costs and who then owns the CO2.”

A nearer-term option is to focus on stripping CO2 from the waste gases produced by industry before it is released into the atmosphere.

CO2 spews from fossil-fuelled power plants, but industries such as steel and cement emit lots of CO2 as well. The chemical reactions needed to turn limestone into cement, for example, set free CO2 gas and cement-making alone releases 7% of all global carbon emissions.

Membranes

The idea is to install membranes that trap CO2, which can then be concentrated and compressed for storage. “Membranes are efficient and can save energy compared to other systems,” said Professor Marco Giacinti Baschetti at the University of Bologna, Italy.

In traditional strategies used by industries such as coal plants, CO2 is captured in special liquids or solid sponge-like structures, but these must then be heated up to release the CO2. This is not needed with membranes. All existing technologies, however, are costly. Current membrane materials are not durable enough and do not separate CO2 well enough to be economically sensible.

Prof. Baschetti runs a project called NANOMEMC2 which is developing a number of different membranes for CO2 capture. In November, the team is to test a new membrane in a Colacem cement facility in Italy.

Developed by project scientists at the Norwegian University of Science and Technology, the membrane is made of hollow fibres, about a millimetre thick, and covered with an extremely thin layer of nanocellulose and polymer mixed with artificial amino acids. The nanocelluose, which is made of miniscule fibres from wood, allows CO2 to permeate, while blocking other gases. The amino acid grabs onto CO2 and pulls it across the membrane.

“Just because you can, doesn’t mean that you should.”
This is yet another stretch application for a special need solution.
There are niche applications for many technologies, and space has cornered that mission extreme. Specialty applications are driven there due to the lack of other options. That is why we developed solar panels, not because they were inexpensive and efficient… the other more efficient and elegant choices weren’t available. This is also why we use mineral scrubbers for air systems. Yes, they work, but they require significant amounts of energy to generate the different mineral lattice structures to create the filters you want. There are naturally occurring sources, but those are inferior to the industrial grade products.
This technology is NOT new. It just hasn’t been cost effective enough to warrant investment in CO2 capture. When there becomes a more lucrative market for CO2, entrepreneurs will collect it and sell it.

There are times when you should. The space station is one example. Another is a nuclear submarine. Both instances are closed environments where the buildup of CO2 would be harmful/fatal if not removed. Applying the technology where there isn’t a real need is just another waste.

[I’m one of the many bubbleheads (submariners) who have lived with CO2 removal technology while submerged for extended periods.]

This is quite energy intensive. All that energy comes from a power plant that produces CO2. Even the renewable energies like solar and wind required an entire industry to build them, all generating CO2. The reason we don’t do this at power plants is that it changes the thermodynamic efficiency of a coal-fired power plant from 35% to 25%. You have increased the cost of electricity substantially, but not really helped much since you are burning 40% more coal to meet the needs of the customer while removing most of the CO2. Much better to just switch to the thorium molten salt reactor – no CO2 at all.

The primary use of CO2 is to enhance the growth of algae, plants, and trees- for free. For any other use large quantities are available from oil processing, fossil fuel power plants, and transportation.
The CO2 can be more cheaply separated right at the point of production from much higher, more economic concentrations. The produce CO2 at about 10 orders of magnitude higher concentration.

Any effort to decrease emissions with the goal of lowering atmospheric CO2 and/or “saving the planet” is patently stupid, as there is no evidence that our emissions have any effect on Earth’s atmospheric CO2 concentration. While overall human emissions have increased dramatically in the last 60+ years, atmospheric CO2 has been rising linearly, indicating the lack of our activities having any effect of CO2.

For that matter, when one considers both IR and Raman spectroscopy, it is apparent that all of the gases in the atmosphere qualify as greenhouse gases (GHG), in which case labeling only on as a GHG is meaningless, except for political reasons. It is stupid to focus on one minor constituent as being uncharge of the atmosphere. It’s junk science to think so.

Efforts to save money by using less of any kind of fuel is fine, but all efforts to fight CO2 are fighting the most valuable life-supporting gas in our atmosphere, oxygen being second because there is plenty of it. However, photosynthesis relies on CO2 and not oxygen, the latter being a waste product of photosynthesis.

Higley,
please try to be more accurate
in the details
(although your conclusion is good):

“there is no evidence that our emissions
have any effect on Earth’s
atmospheric CO2 concentration.”

WRONG:
Humans have added a lot of CO2 to the atmosphere
since 1940, and some before then too.
.
.
“For that matter, when one considers both
IR and Raman spectroscopy,
it is apparent that all of the gases
in the atmosphere
qualify as greenhouse gases (GHG),
in which case labeling only on as a GHG
is meaningless”

WRONG:
Oxygen and nitrogen don’t qualify
as greenhouse gases,
by the standard definition
used to label water vapor,
CO2 and methane
as greenhouse gases
.
.
.
The details matter, because they
are easily refuted … making people
ignore your reasonable conclusion.

.
.
I see CO2 is a beneficial gas,
and our planet’s plants
would significantly benefit
from double to triple
the current CO2 level.

Greenhouse owners
know what CO2 enrichment does,
but what could they possibly know
about plants?

Adding more CO2 to the air,
with clean burning fossil fuels
(there are exceptions)
is the best thing
humans have ever done
(inadvertently)
to improve life on our planet.

Real science supports
MORE CO2 in the air.

Junk climate science
has a leftist political agenda,
and has nothing to do
with real science

If O2 and N2 didn’t contain heat we would freeze. By that count they are indeed greenhouse gases. They may not absorb much LWIR directly but through collisions with the other GHG’s they provide thermalized heat. The atmosphere does indeed need more CO2 NOT less.

Can’t plant trees because we need that land to plant solar farms and wind farms. Remember boys and girls, acres and acres of mined aluminum, mined rare earth metals, toxic chemicals, and concrete is greener than acres and acres of trees.

Why plant them? They have seeds and have evolved to germinate and grow all by themselves. Why should we plant them? That’s just virtue-signalling on our part to make us feel better on a false pretense. I’m sure the trees much better at tree reproduction. We’d just pick favorites and winners and losers and wreck the biodiversity mix.

It would be interesting to collate the amount of effort, fuel, electricity and wages that go into the cultivation of seedlings, then to drive them out to get planted by volunteers and watered a couple of time.

I’ll be it’s surprising. All the while, as you say, trees will self propagate at a maddening rate if you own acreage.

Where it might be practicable is in areas significantly devoid of trees now. e.g. the Sahel is greening along with many other areas – rainfall in the area could be improved by a minor effort to planet drought tolerant trees and ground cover.

People seem to have forgotten that many deserts were created by stripping vegetation – which is why so many of the major ones coincide with where sheep and goats have been major domestic animals. Putting trees back there and spending far less than a year worth of Church of AGW tithes could start a reversal of desertification that could change millions of lives.

*impractical .. impracticle was actually the suggested word on autocorrect and I hit enter before seeing it. Thank you Steve Jobs. I think English should go to phonetic spelling of everything. At least my son must think so since that is how he spells a lot of words.

As far as planting trees, I might bring up most everything immediately around our homes is planted vegetation. We are a planting species. However on a larger scale, you see it both ways: tree farms that have GMO pines bred for fast growing planted in neat little rows and the entire Smoky Mountain National Park that was mostly clear cut 100 years ago and was left in a lot of cases to sprout on its own.

The only problem with allowing the area to recover on its own is the lack of seeds, since in most cases the areas have been burned or clear cut and the only seeds to come in would be carried by birds, animals or the wind. Here in North Carolina, you get the scrub brush first, then the pines and finally the hardwoods. It takes a century or more to get to a normal mixing, even with the abundant rainfall and long growing season we have.

Or you could do the obvious thing of replacing fossil fuel power plants with cheaper molten salt nuclear reactors. I realize that this approach is far too simple, direct and cost effective, which, of course, dooms it for Rube Goldberg inventors.

I am amazed to find out that CO2 is just separated out and dumped into space in the space station. Hello — it has two oxygen molecules, which in a sensible system would be separated from the C and put back into the space station’s air supply! The sun provides plenty of free energy to do this.

I want to be on record as saying that concentrating CO2 underground is just a horrible, horrible idea. First, you deny the living systems of this Earth the benefits of having the CO2. Secondly, you create a huge risk to nearby living things should the “container” breach and the CO2 exits as a deadly bubble, as has happened a few times in recorded history. Third, there will be active expenses to run this silly industry, overhead expense and lost opportunity cost, a total waste of money to solve a non-problem. It’s lose, lose, lose, all the way down. So of course, your average Climate Scientologist will love the power and money going into their sphere of influence that this kind of idea engenders.

Yes. It often strikes me as curious that some people who swear that you can’t effectively store small amounts of solid nuclear waste in stable geological formations are often the same people who think that you can store enormous a mounts of a compressed gas in similar structures.
It’s just not logical, Captain.

CO2 is important for Life. Do not waste it! All animals incl. humans get the Carbon and Oxygen from plants that needs CO2! Like someone already wrote, plant a tree! In Finland we plant 160 million trees a year.

I hear ya ,mate! Here in Canada we have literally billions of the damn things. Can’t even see the countryside for the damn things. On a long drive you can’t nod off for even a second cause they’ll get ya!

Only 160million? That’s not many. Here in NZ our leftie politicians have pledged to plant a billion. My “back of envelope” calculation shows it cannot be done, and they have no idea just how big a number a billion is. And totally pointless to try to absorb CO2, when we need much more of it. I quite like the idea of 2 Italian-sounding scientists freezing in Scotland working on a useless project, apart from the funding they will be receiving from unwilling taxpayers!

I rather suspect CO2 discharded from a near Earth orbiting craft would mostly find it’s way back to Earth’s atmosphere…. for the same surprising reason Earth’s atmosphere doesn’t just fly off into space. Maybe the whole thing was supposed to be just a joke.

The only somewhat practical solution is to enrich air to 95% oxygen, burn methane with the enriched mix in a turbine, include a CO2 recycle to keep the turbine cool and inject the cool effluent (mostly CO2 with a bit of nitrogen) in an old oil field, or cool it to turn the CO2 into a liquid phase, separate the nitrogen gas, and inject supercritical CO2 in a deep saline aquifer. This scheme could be viable with the CO2 disposal subsidy. I think.

Has the Warmers lobby ever admitted that CO2 is also “Plant food”, thus they are proposing to cause a reduction in the fertilizer, with possibly millions of deaths from starvation in the Third World countries.

And Charles is right about the thermodynamics. In order to expel a few billion tons of CO2 into space you have to accelerate said billions tons to escape velocity. The mechanics are just the same for gssses as for solid bodies.

Spend billions if not trillions to create an artificial tree? Why not engineer algae to grow like fungus and paint the inside of the space capsule with it? That way you would have O2 producing CO2 eating paint? What a complete waste of money this battle against climate change has become. Someone needs to put a stop to this endless waste of resources.

CO2isLife:
Look at that photo. The place is a bomb-site. You bring a ‘hot first date’ home to that and it’ll be ‘cold last date’ I suspect there is plenty algae going on in there already.

Somewhat similarly and staying with the photo, it has been said that:
“In space, no-one can hear you scream”

Is there anything else you cannot hear – is that why a 6 inch plastic duct is coming away from his backside?
And where did his hair go? Don’t tell me. Space Aerodynamics.
I see NASA written all over this

I’ve just worked it out… The ducting leads to Carbonoxide Life Processes Laboratory, i.e where the algae is growing.
AKA; The kitchen and where Ancell Keys formulated the K-ration.
Hence why anyone forced into ‘consuming’ that junk simply kept the cigarettes it contained (for later) and threw the rest away.
So that’s it, he set his hair on fire lighting a cigarette.

Maybe a CO2 based fire extinguisher would have been handy.
yup
NASA organised that one……..

Why get rid of a beneficial gas? Perhaps it’s necessary in the enclosed environment of the space station, but the atmosphere in submarines regularly exceeds 5000 parts per million and the crews suffer no ill effects.

“Because CO2 is very dilute in ambient air, technology such as giant fans would be needed to suck it towards the stations”
Hi Stefano, giant fans are already there masquerading as the ‘wind turbines electricity generators’.

Another stupid idea from Prof. Stefano Brandani (PhD in Chemical Engineering) who may have had a perceptible degree of intelligence in his younger days, not unusual among anthropocentric climatophobic community.

I think that the distinguished Prof has a more sophisticated plan in mind. The wind turbines will dissipate airflow , but provide energy . So, from one part of our landscape , covered by 400 ft wind turbines , energy will flow via pylons to another part where the energy will be used to power 400 ft giant fans directing air into 400 ft wind tunnels at the end of which are filters of zeolites ( which are manufactured from hot, energy consuming hydrothermal solutions of alumino silicates ( a process devised by my old dept head at IC , the Nobellist Prof Barrer)) . Since so much of the wind farm energy goes into powering the giant fans , gas power stations are set up to actually power homes , offices and factories ( not to mention 20 million electric cars promised for UK).
You have to be very clever to devise such stupidity .
I am glad that we sceptics are seldom credited with such intellectual prowess .

God save us from people who want to use some form of technology to correct an issue like CO2. Here in Canada, while we continue to pump tons of effluent into the water (hello BC, the “greenest” Provincial government and the biggest dumper), we have the Clown Prince of Ottawa promising us a “carbon” tax that will bring you more money than it costs (if you fall into a certain class) while ignoring the fact that they will not be taxing carbon but the use of hydro-carbons. The pundits say it will not be an election issue, because people will just accept it…I guess that is what Marcon thought in France as well.

Concentrating CO2 with membranes is not a new idea. It’s been under development for years. The reason it has taken years is because it is highly energy intensive and requires hundreds of thousands of square feet of membranes in thousands of pressure vessels, all with interconnecting piping. Oh, and the acids, organics and particulates in the stack gases tend to wear out and plug the pores in the membranes.

Using zeolites for CO2 capture is also not new. They have been researched, along with other manufactured “cage” structures to capture CO2 molecules. They are a variety of “pressure swing” absorbents in one use and heated regeneration in another. A ctm says, they are thermodynamically challenging.

“When astronauts aboard the International Space Station (ISS) exhale carbon dioxide (CO2), it’s removed from the air and pumped into space.”
Wait a minute. Two significant problems here. First, if you pump all that CO2 into space, the background temperature will increase from 4K to 5.5K. That will destabilize celestial thermodynamics. Second, you don’t pump things into space. Space sucks. For the \sarc concerned, I was considering appending \sarc to my comment but decided against it.

Can you imagine? We could design a system that systematically starves the entire planet of food? Let’s get right on it and THEN afterwards, we can kick back and congratulate ourselves on our accomplishment while sitting in space suits on our new planet, COMING SOON TO YOUR NECK OF THE WOODS– > MOON 2.

What the everloving F*$K? (yes custerisks folks!)

Why in the world would anyone give this idea anything other than a scoff and a look of incredulity. It reminds me of one of the best lines (ok, there were several…) in Jurassic Park: …”your scientists were so busy wondering IF they could do it, they never bothered to ask themselves if they SHOULD”.

A similar thought had occurred to me as well with the exception of
While expelling CO2 from an enclosed biosphere will stop levels from becoming the unhealthy 6-7% concentration level, it also removes the needed O2 along with its partner C

Thanks for replying. Just wondering. Yes, zeolites are a group of naturally occurring minerals each with a specific chemical composition, orderly atomic arrangement and resulting crystalline structure. Examples are heulandite, stilbite, natrolite, laumontite. I suppose there is a whole chem engineering field associated with manufactured zeolite. Maybe the ISS material is manufactured mineral.

I remember when the DOE spent ~ billion $ at the Hanford nuclear site with the intent to contain radioactive waste inside of one of the continents greatest aquifers using zeolites. Finally, honest professionals prevailed with the obvious – perfect containment (weakly bonded within zeolite mineral lattice – placed in an active regional aquifer was a pipe dream. Some contained and some not is unacceptable for plutonium and other rad waste. Government science project.

Gas is not the same as a liquid or solid. Do these scientists really think that we can sequester 42 billion tons of CO2 underground, every year, forever? Do they know how prone to leakage the planetary crust is? Do they know how difficult it is to take a gas and cram it into a comparable size space from which the liquid or solid hydrocarbons were removed?

Lots of things can be made to absorb CO2, concrete for example. It’s not even close to being original. I’ve seen better science fair projects, a lot better.

CO2 is converted in a way that can be stored, used or sold to recuperate a part of the expenses of operating the device. link

99.9% of these hair brained CO2 capturing schemes give no thought to economics. That means a couple of high school science fair entrants are smarter than 99.9% of scientists who propose CO2 capture schemes.

Not to worry – the climateers would never support this.
The globalists only want $$$ (a.k.a. cap & trade).
The politicians only want the ‘fear votes’.
A significant subset of scientists only want their research money, not a solution that puts them out of business.
And the low information masses have no idea what they really want, except perhaps to blather on about the sky falling.

An older (2015) reference says that NASA used have a maximum such limit of 7,000 ppm on the manned ISS.

I can only speculate that the pragmatism of ISS operations engineers has discounted all of the dire warnings from NASA climate “scientists” about humans living with a doubling of current atmospheric CO2 levels (from 410 ppm today to 820 ppm one hundred years from now).

SO the idea is to heat and cool, over and over, beds of material to move the CO2 to a point it can be stored.

Does it also treat the CO2 from the power generation required to run the heating and cooling? Because, with my limited knowledge of the real world and physics, I am betting there’s a net loss to this system, which means this will never work.

Incredibly stupid comment contained in the above article: “Another is to design materials that can remove the CO2 that is already in the atmosphere or before it’s expelled. The problem is that no one has quite worked out how best to do this – yet.”

Well, maybe no person has quite worked out how best to do this because Mother Nature evolved the “solution” starting some 2.5 billions or so years ago: it is called cyanobacteria, or blue-green algae. These microbes conduct photosynthesis: using sunshine, water and carbon dioxide to produce carbohydrates and oxygen. In fact, all the plants on Earth—including grasses and trees—incorporate symbiotic cyanobacteria (known as chloroplasts) to do their photosynthesis for them even today.

I can confidently state that humans will never exceed the overall efficiency that cyanobacteria have evolved on removing atmospheric CO2 on a global scale, while at the same time converting it into some things that humans find quite useful: oxygen and food.

If Climate Alarmist’s really believed their BS (instead of just wanting climate cash) they would push for fertilizing the oceans and seas with trace amounts of iron dust or having shops tow barges of steel wool. The plankton in the water would increase its conversion of CO2 to O2, and as a ‘side’-effect provide tons of food for fish at the very base of the food chain, helping every species above. Might I also add, that this would also offset the effects of commercial fishing. Basically win-win-win, but since they don’t really want to help the biosphere, but only want to help themselves to our money, they block the idea at every turn. It was used by a Native Canadian tribe on the west coast for 2 years and got record salmon catches both years, before the government came in and enforced poverty on them.

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